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Making Every Species Count

by
Mimi Padmabandu
| Feb 11, 2013

Imagine living in a bioliterate world—one in which you could learn everything about any organism immediately. Paul Hebert, Scientific Director of the International Barcode of Life (iBOL) project, envisions a day when you and your children notice an unusual plant in your backyard, “scan” its DNA, and learn the name, if it’s poisonous or endangered, and whether it resides in a natural habitat or is an invader. This imagined scenario is a goal of the iBOL initiative to sequence 500,000 species—the largest biodiversity genomics research program ever undertaken. Begun in 2010, this collaboration of researchers uses DNA barcoding to identify species based on unique genomic “signatures.” Their efforts to build a comprehensive database of organisms are bringing the idea of a bioliterate world out of science fiction and into reality. butterfly

When efforts to classify organisms first began, early scientists hypothesized that there were a few thousand species on our planet. Researchers, field explorers, and ordinary citizens have identified approximately 1.7 million species to date, but the total number remains unknown. The best estimate available today puts the number around 8.7 million species, but some believe there could be as many as 100 million species on Earth.

Historically, the methods of classifying organisms relied on morphological features like shape, size, and color. The advent of DNA sequencing is changing the way we look at how organisms are related genetically, and how genetic changes occur over time. DNA barcoding leverages sequencing technology by using a short stretch from a stable part of the genome to distinguish species from one another, similar to the way a supermarket scanner distinguishes products using a barcode label. Tissues from natural history museums, herbaria, zoos, aquaria, frozen tissue collections, seed banks, and other repositories are common sources of samples for DNA barcoding. The goal of DNA barcoding is the construction of an enormous, online, freely available database of sequences and other identifying information called the Barcode of Life Database (BOLD).

“If we’re going to understand life on this planet, we’re not going to do it through morphology alone,” says Hebert. “We have to look towards this transition and connecting DNA sequences to the organisms on our planet if we’re going to understand their distribution and diversity.”

How effective is the DNA barcoding method? Using Hebert’s favorite order, Lepidoptera (moths and butterflies), as a model, DNA barcoding effectively discriminates between species in 98% of cases, also identifying species that were overlooked using traditional morphological analysis.

Biodiversity projects like iBOL will have a huge impact on human health, forensics, environmental surveillance, pest identification, and interception of species invasion. Besides supporting conservation and taxonomy efforts, the Barcode of Life project aims to build bioliteracy awareness that resonates with everyone, not just biological scientists—after all, our children will continue discovering plants and animals in the backyard with their children. You can learn more about what's happening with barcoding at the Barcode Blog.

 


Image courtesy of Christian Meyn / FreeDigitalPhotos.net

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